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Production scientifique
Cellule Hygiène et Sécurité
(12) Production(s) de l'année 2016
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Transport of ions and molecules inside carbon nanotubes : towards the detection of individual biomolecule
Auteur(s): Yazda K., Tahir S., Michel T., Thibaud Jean-Baptiste, Loubet Bastien, Manghi Manoel, Palmeri J., Henn F., Jourdain V.
(Affiches/Poster)
5ème Journées Scientifiques du LabEx NUMEV (Montpellier, FR), 2016-10-05
Ref HAL: hal-01950212_v1
Exporter : BibTex | endNote
Résumé: We present experimental and theoretical results for the transport of ions and molecules inside carbon nanotubes.
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Evidence of selective cation transport through sub-2 nm single-walled carbon nanotubes
Auteur(s): Yazda K., Tahir S., Michel T., Henn F., Jourdain V.
(Article) Publié:
Mrs Advances, vol. 1 p.2079-2084 (2016)
Ref HAL: hal-01928862_v1
DOI: 10.1557/adv.2016.323
WoS: WOS:000412635300009
Exporter : BibTex | endNote
Résumé: The electrophoretic transport of ions through single wall carbon nanotubes (SWCNTs) of diameters between 1.2 and 1.8 nm was studied for different monovalent chloride salts using microfluidic devices incorporating either a single or a few CNTs in parallel. The ionic conductance was found to be about one order of magnitude higher than expected from a simple electro-migration behavior without any surface effect. Importantly, the ionic conductance measured for different cations did not scale with their bulk electrophoretic mobility thus indicating a probable selective cation transport through these sub-2 nm SWCNTs. The transport of Na+ was notably found to be favored in comparison to that of Li+ and Cs+ or K+ . These results highlight the influence of steric and surface effects induced by the nano-confinement on the transport of ions through sub-2 nm SWCNTs.
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Voltage-Activated Ion Transport through Single-Walled Carbon Nanotubes
Auteur(s): Yazda K., Michel T., Tahir S., Picaud Fabien, Loubet Bastien, Manghi Manoel, Palmeri J., Henn F., Jourdain V.
Conference: MRS Fall Meeting (Boston, US, 2016-11-28)
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In situ study of single-walled carbon nanotube growth in an environmental scanning electron microscope.
Auteur(s): Mehedi H-A, Ravaux J, Tahir S., Podor Renaud, Jourdain V.
(Article) Publié:
Nanotechnology, vol. 27 p.505701 (2016)
Ref HAL: hal-01624816_v1
PMID 27855127
DOI: 10.1088/0957-4484/27/50/505701
WoS: 000412645900001
Exporter : BibTex | endNote
4 Citations
Résumé: Monitoring individual single-walled carbon nanotubes (SWCNTs) during their growth is a highly sought-after goal in view of understanding the processes involved in the nucleation, elongation and termination which ultimately control the diameter and chiral selectivity. Here, we report on the first truly in situ observations of SWCNT growth in an environmental scanning electron microscope (ESEM). The CNT growth from lithographically patterned catalysts was investigated as a function of the catalyst type (Fe, Co or Ni), temperature, type of precursor (ethanol or acetylene), gas phase composition and pressure, and pretreatment conditions, and we report on the most appropriate conditions for SWCNT growth in ESEM conditions. We show that this approach allows the observation at the submicron scale of the different steps of the nanotube synthesis including the catalyst reduction, the growth and percolation of the nanotube network, and the deposition of individual nanotubes grown in the gas phase on the substrate. Despite these obvious advantages, we identified a few limitations which will need to be tackled for fully taking advantage of the approach, for instance for monitoring the growth of individual SWCNTs by ESEM, including the short lifetime of the catalyst nanoparticles, the preference for kite growth (by opposition to surface growth) and the influence of the electron beam on the nanotube growth.
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Aggregation Control of alpha-Sexithiophene via Isothermal Encapsulation Inside Single-Walled Carbon Nanotubes
Auteur(s): Gaufres Etienne, Tang Nathalie Y. -W., Favron Alexandre, Allard Charlotte, Lapointe Francois, Jourdain V., Tahir S., Brosseau Colin-Nadeau, Leonelli Richard, Martel Richard
(Article) Publié:
Acs Nano, vol. 10 p.10220-10226 (2016)
Ref HAL: hal-01436065_v1
DOI: 10.1021/acsnano.6b05660
WoS: WOS:000388913100051
Exporter : BibTex | endNote
14 Citations
Résumé: Liquid phase encapsulation of α-sexithiophene (6T) molecules inside individualized single-walled carbon nanotubes (SWCNTs) is investigated using Ramanimaging and spectroscopy. By taking advantage of the strong Raman response of this system, we probe the encapsulation isotherms at 30°C and 115°C using a statistical ensemble of SWCNT deposited on a Si/SiO2 substrate. Two distinct and sequential stages ofencapsulation are observed: Stage 1 is a one-dimensional (1D) aggregation of 6T alignedhead-to-tail inside the nanotube and stage 2 proceeds with the assembly of a second row, giving pairs of aligned 6Ts stacked together side-by-side. The experimental data are fitted using both Langmuir (type VI) and Ising models, in which the single-aggregate (stage 1) forms spontaneously whereas the pair-aggregate (stage 2) is endothermic in toluene with formation enthalpy of 8Hpair = 260±20 meV. Tunable Raman spectroscopy for each stage reveals a bathochromic shift of the molecular resonance of the pair-aggregate, which is consistent with strong inter-molecular coupling and suggestive of J-type aggregation. This quantitative Raman approach is sensitive to roughly 10 molecules per nanotube andprovides direct evidence of molecular entry from the nanotube ends. These insights into the encapsulation process guide the preparation of well-defined 1D molecular crystals having tailored optical properties.
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Evanescent Waves Nuclear Magnetic Resonance
Auteur(s): Halidi E. M., Nativel Eric, Akel M., Kenouche S., Coillot C., Alibert E., Jabakhanji B., Schimpf Remy, Zanca M., Stein Paul, Goze-Bac C.
(Article) Publié:
Plos One, vol. 11 p.e0144483 (2016)
Texte intégral en Openaccess :
Ref HAL: hal-01394852_v1
DOI: 10.1371/journal.pone.0144483
WoS: WOS:000367888100010
Exporter : BibTex | endNote
Résumé: Nuclear Magnetic Resonance spectroscopy and imaging can be classified as inductive techniques working in the near- to far-field regimes. We investigate an alternative capacitive detection with the use of micrometer sized probes positioned at sub wavelength distances of the sample in order to characterize and model evanescent electromagnetic fields originating from NMR phenomenon. We report that in this experimental configuration the available NMR signal is one order of magnitude larger and follows an exponential decay inversely proportional to the size of the emitters. Those investigations open a new road to a better understanding of the evanescent waves component in NMR with the opportunity to perform localized spectroscopy and imaging.
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